Discolouration Monitoring, Interpretation & Asset Deterioration Management - Delivering the success of PODDS research

PODDS has delivered valuable practical research outputs from exploration of all aspects of discolouration, coupled with discussion and debate that is informed by wide ranging real world examples and situations from multiple project partners. The outcomes have seen delivery of evidence based pioneering strategies, including industry accepted monitoring and modelling tools, widespread inclusion in PR19 submissions, long term operational benefits, improved risk management and significant cost-savings with improvements in levels of service and customer satisfaction.  In July 2019 OFWAT published their emerging strategy for regulating water in which they state “that the adoption of innovative approaches is key to delivering long-term resilience… in a cost-effective and sustainable way” and a desire “to see companies work more effectively together and with their supply chain to better tackle these challenges.”  These declarations echo the work and achievements of the PODDS project since its inception. To sustain and grow PODDS delivered advances and promote desirable pro-active and efficient water quality management strategies, a two year #PODDS project is proposed to continue the research and development, current company bespoke support and facilitate sharing of best practices. The research will focus on improving understanding of asset deterioration rates that are critical to inform operational and maintenance schedules whilst investigating value obtainable from location, extent, hosting and interpretation of data from network monitoring


PODDS Visual Summary - A useful summary document to share PODDS understanding/

A Research Feature suitable for a general audience about PODDS and titled "How two engineers are solving the UK's number one water quality complaint" is linked here...



VCDM Introductory Course - video and Powerpoint slides

VCDM Online Modelling - test file and maintenance planner


PODDS Related Company Publications

1: June 2016 - Scottish Water Vision magazine "...£15 million saving..."

2: September 2016 - Northumbrian Water in Water & Wastewater Treatment "...90% capital cost saving..."

PODDS Epanet model parameters can be seen here.

PODDS Epanet Model, Discolouration Risk Analysis Tool and PODDS Epanet Manual available here.

Contaminant Ingress Distribution (CID) videos


Regulating Discolouration in the UK. This document has been produced to stimulate discussion regarding the current regulation of discolouration related issues in the UK. It attempts to capture some key aspects that have arisen during PODDS events. The questions raised are substantive and potentially controversial.

NTU Equivalence - set of plots that demonstrate how turbidity correlates with iron and manganese from national and international PODDS trials.


Some examples of PODDS mediated savings are highlighted in table (click table to get pdf document)





1. 25th February 2020, PLB E05, University of Sheffield: Agenda, presentation and minutes

2. 3rd June 2020, Video-conference, Agenda, presentation and minutes

2. 8th September 2020, Video-conference, Agenda, presentation and minutes





Kat Fish, Nik Reeves-McLaren, Stewart Husband & Joby Boxall J (2020) Unchartered waters: the unintended impacts of residual chlorine on water quality and biofilms. npj Biofilms and Microbiomes (2020) 6:34 ; https://doi.org/10.1038/s41522-020-00144-w

Gonzalo Del Olmo, Stewart Husband, Carmen Sanchez Briones, Adela Soriano, Carolina Calero Preciado,Javier Macian, isabel Douterelo (2020). The microbial ecology of a Mediterranean chlorinated drinking water distribution systems in the city of Valencia (Spain).Science of the Total Environment, https://doi.org/10.1016/j.scitotenv.2020.142016 (in print)

A. V. Doronina , S. P. Husband , J. B. Boxall & V. L. Speight (2020) The operational value of inlet monitoring atservice reservoirs, Urban Wter Journal, https://doi.org/10.1080/1573062X.2020.178747

M. Al-Saffar & S. Husband (2020): Long-term discolouration modelling for castiron mains, Urban Water Journal, DOI: 10.1080/1573062X.2020.1769689

Weirong Xu, Xiao Zhou, Kunlun Xin, Joby Boxall, Hexiang Yan and Tao Tao (2020) Disturbance Extraction for Burst Detection in Water Distribution Networks Using Pressure Measurements. Water Resources Research 56. doi.org/10.1029/2019WR025526

Silva Carpitella, Gonzalo Del Olmo, Joaquin Izquierdo, Stewart Husband & Joby Boxall (2020) Decision-Making Tools to Manage the Microbiology of Drinking Water Distribution Systems. Water 12. https://www.mdpi.com/2073-4441/12/5/1247/pdf, doi:10.3390/w12051247

Isabel Douterelo, Bas E Dutilh, Ksenia Arkhipova, Carolina Calero, Stewart Husband (2020). Microbial diversity, ecological networks and functional traits associated to materials used in drinking water distribution systems.Water Research (in print)

Killian Gleeson, Joby Boxall, John Gaffney, Neeraj Shah, Stewart Husband (2020). Automated quality assurance methodology to validate water distribution system time series data. HIC2020, Mexico

Frances C. Pick, Katherine E. Fish, Catherine A. Biggs, Jonathan P. Moses, Graeme Moore, Joby B. Boxall. Application of enhanced assimilable organic carbon method across operational drinking water systems. Research Article | published 06 Dec 2019 PLOS ONE https://doi.org/10.1371/journal.pone.0225477

I. Sunny, S. Husband, J. Boxall, J., 2019. Impact of Hydraulic Interventions on Chronic and Acute Material Loading and Discolouration Risk in Drinking Water Distribution Systems. Water Research, https://doi.org/10.1016/j.watres.2019.115224.

W. Furnass, S. Mounce, S.Husband, R. Collins, J. Boxall, (2019). Calibrating and validating a combined accumulation and mobilisation model for water distribution system discolouration using particle swarm optimisation. SMART WATER, Springer Open, https://doi.org/10.1186/s40713-019-0015-z

CCWI 2019, Exeter, UK;

1. The Operational Value of Inlet Monitoring at Service Reservoirs, A. Doronina, S. Husband, J. Boxall & V. Speight

2. Discolouration Modelling, S. Husband, J. Boxall & M. Al-Saffar

3. Long-Term Discolouration Modelling for Cast Iron Mains, M. Al-Saffar & S. Husband

S. Husband, Water Quality Technology Conference® & Exposition - Nov. 11-15, 2018| Toronto, Canada - presentation

I. Douterelo, R.L. Sharpe, S.Husband, K. Fish, J. Boxall, (2018). Understanding microbial ecology to improve management of drinking water distribution systems. WIREs Water, https://doi.org/10.1002/wat2.1325

K. Fish, J. Boxal, (2018).' Biofilm Microbiome (Re)Growth Dynamics in Drinking Water Distribution Systems Are Impacted by Chlorine Concentration'. Frontiers in Microbiology, https://doi.org/10.3389/fmicb.2018.02519

S. Husband, K. Fish, M. Blokker, J. Boxall, (2018). 'Understanding hydraulics and biofilm development to target flushing resources and manage discolouration in drinking water distribution systems' WQTC 2019, Toronto, Canada

I, Douterelo, C. Calero, S. Husband (2018) 'Monitoring Biofilm Communities in Operational Drinking Water Distribution Systems and the Impact on Water Quality' WDSA-CCWI2018, Kingston, Canada

S. Husband, J. Boxall (2018) 'Understanding Material Accumulation and Discolourati on Risk in Distribution Networks' WDSA-CCWI2018, Kingston, Canada

K. Fish, S. Husband, J. Boxall (2018) 'The Impact of Chlorine Concentration on the Discolouration Response of Biofilms in Drinking Water Distribution Systems' WDSA-CCWI2018, Kingston, Canada

M. Al-Saffar, S. Husband (2018) 'Optimising Flow Conditioning in Operational Trunk Mains for Discolouration Risk Reduction and Maintaining Network Resilience' WDSA-CCWI2018, Kingston, Canada

I. Sunny, s. Husband, J. Boxall (2018) 'Seasonal Temperature and Turbidity Behaviour in Trunk Mains' WDSA-CCWI2018, Kingston, Canada

E. Kazemi, S. Mounce, S. Husband, J. Boxall (2018) 'Predicting turbidity in water distribution trunk mains using nonlinear autoregressive exogenous artificial neural networks' HIC 2018, Palermo, Italy

R.L Sharpe, C. Biggs, J.Boxall (2017). ' Hydraulic conditioning to manage potable water discolouration' Proceedings of the Institution of Civil Engineers - Water Management 0, 1-11, http://dx.doi.org/10.1680/jwama.16.00038

S. Husband, J. Boxall (2017) 'Real time modelling of pipe wall material and managing the discolouration risk in distribution systems" WQT_2017, Portland, Oregon USA

I. Sunny, S. Husband, G. Moore, N. Drake, K. Mckenzie, and J. Boxall. (2017) 'Discolouration Risk Management and Chlorine Wall Decay" CCWI_2017, Sheffield

D.M. Cook, P.S. Husband (2017) 'Rusby Wood a Smart Network for Sustainable Discolouration Risk Reduction' CCWI_2017, Sheffield

I. Sunny, S. Husband, N. Drake, K. Mckenzie, and J. Boxall. (2017) 'Quantity and quality benefits of in-service invasive cleaning of trunk mains" Drinking Engineering Science, 10, 1-8 https://doi.org/10.5194/dwes-10-1-2017

S. Husband, J. Boxall (2016) 'Corrosion and Water Quality" Water & Sewerage Journal 96, pp 42,43

S. Husband, G. Thomas, J. Boxall (2016) 'Operational Strategies for Sustainable Drinking Water Distribution System Maintenance" WQT_2016 Conference, Indianopolis, Indiana USA

S. Husband, J. Boxall (2016) 'Understanding and Managing Discolouration Risk in Trunk Mains' Water Research, Vol 107, pp127-140 doi.org/10.1016/j.watres.2016.10.049

S. R. Mounce, E. J. M. Blokker, S. P. Husband, W. R. Furnass, P. G. Schaap, J. B. Boxal (2016) 'Multivariate data mining for estimating the rate of discolouration material accumulation in drinking water systems' Journal of Hydroinformatics, 18, 96-114. DOI: 10.2166/hydro.2015.140

Blokker, E. J. M., Furnass, W. R., Machell, J., Mounce, S., Schapp, P. G. & Boxall, J. 2016. Relating Water Quality and Age in DrinkingWater Distribution Systems Using Self-Organising Maps. Environments [Online], 3, 10 DOI:10.3390/environments3020010

Fish, K., Osbourn, A. & Boxall, J. (2016). Characterising and Understanding the Impact of Microbial Biofilms and the Extracellular Polymeric Substance (EPS) Matrix in Drinking Water Distribution Systems. Environmental Science: Water Research & Technology. DOI: 10.1039/c6ew00039h

Husband, P. S., Fish, K., Douterelo, I. & Boxall, J. (2016). Linking discolouration modelling and biofilm behaviour within drinking water distribution systems. Water Science & Technology: Water Supply, 16.4, 942-950 DOI: 10.2166/ws.2016.045

D.M. Cook, P.S. Husband & J.B. Boxall (2016) 'Operational management of trunk main discolouration risk' Urban Water Journal DOI: 10.1080/1573062X.2014.993994

Mounce, S. R., Mounce, R. B. and Boxall, J. B. (2016). Case-based reasoning to support decision making for managing drinking water quality events in distribution systems. Urban Water Journal. 13 (7), pp. 727-738

Mounce, S. R., Gaffney, J. W., Boult, S. and Boxall, J. B. (2015). Automated data driven approaches to evaluating and interpreting water quality time series data from water distribution systems. ASCE Journal of Water Resources Planning and Management. Vol 141 (11), pp. 1-11.

Blokker, E. J. M. & Schapp, P. G. 2015. Particle accumulation rate of drinking water distribution systems determined by incoming turbidity. Procedia Engineering, 119 (CCWI), 290-298.

Jones, S., Collins, R. & Boxall, J. 2015. Do transients contribute to turbidity failures of water distribution systems? Pressure Surges 2015, . Dublin, Ireland.

Ellis, K., Mounce, S., Edwards, J., Speight, V., Jakomis, N. & Boxall, J. 2015. Interpreting and estimating the risk of iron failures. Procedia Engineering 119 (CCWI), 299-308.

S. Husband, M. Jackson & J. Boxall (2015) 'Identifying Material Accumulation Processes in Drinking Water Distribution Systems with Extended Period Epanet MSX Turbidity Simulations' Procedia Engineering Vol 119 pp 398-406 doi:10.1016/j.proeng.2015.08.901

S. Husband, J. Boxall (2015) 'Predictive water quality modelling and resilience flow conditioning to manage discolouration risk in operational trunk mains' IWA Publishing Journal of Water Supply: Research and Technology-AQUA 64.5, pp529-542 doi: 10.2166/aqua.2014.042

S. Husband, I. Douterelo, K. Fish, J. Boxall (2015) 'Biofilms and Discolouration Material Accumulation Processes in Drinking Water Distribution Systems and Modelling the Hydraulic Mobilisation' IWA Specialized Conference Biofilms in drinking water systems Arosa, Switzerland August 2015

S. Husband, M. Jackson & J. Boxall (2015) 'Identifying Material Accumulation Processes in Drinking Water Distribution Systems with Extended Period Epanet MSX Turbidity Simulations' 13th Computer Control for Water Industry Conference, CCWI, Leicester, UK September 2015

Fish, K., Collins, R., Green, N., Sharpe, R. L., Osbourn, A. & Boxall, J. (2015). Characterisation of the Physical Composition and Microbial Community Structure of Biofilms within a Model Full-Scale Drinking Water Distribution System. PLOS ONE, 10.

Douterelo, I., Boxall, J., Dienes, P., Sekar, R., Fish, K. & Biggs, C. (2014). Methodological approaches for studying the microbial ecology of drinking water distribution systems. Water Research, 65, 134-156.

Douterelo, I., Sharpe, R. L. & Boxall, J. (2014). Bacterial community dynamics during the early stages of biofilm formation in a chlorinated experimental drinking water distribution system: implications for drinking water discolouration. Journal of Applied Microbiology, 117, 286-301.

S.R. Mounce, P.S. Husband, W.R. Furnass, J.B. Boxall (2014) 'Multivariate data mining for estimating the rate of discolouration material accumulation in drinking water systems' 16th Conference on Water Distribution System Analysis, WDSA 2014, Bari, Italy (Conference presentation can be found here)

I.Douterelo, S. Husband, J.Boxall (2014) 'The bacteriological composition of biomass recovered by flushing an operational drinking water distribution system' Water Research Volume 54, 1 May 2014, Pages 100-114, http://dx.doi.org/10.1016/j.watres.2014.01.049

Furnass, W. R., Collins, R. P., Husband, P. S., Sharpe, R. L., Mounce, S. R. and Boxall, J. B. (2014)
Modelling both the continual erosion and regeneration of discolouration material in drinking water distribution systems. IWA Water Science and Technology: Water Supply, Vol 14 (1), pp. 81-90.

S.Husband, J.Mistry, J.Boxall (2013) 'Modelling and flow conditioning to manage discolouration in trunk mains' 12th International Conference on Computing and Control for the Water Industry, CCWI2013, Perugia Italy 2-5th September 2013

I.Douterelo, R.L. Sharpe, J.Boxall (2013) 'Influence of hydraulic regimes on bacterial community structure and composition in an experimental drinking water distribution system' Water Research Volume 47, Issue 2, 1 February 2013, Pages 503–516, http://dx.doi.org/10.1016/j.watres.2012.09.053

W. R. Furnass , R. P. Collins, P. S. Husband, R. L. Sharpe, S. R. Mounce and J. B. Boxall (2012) 'Modelling both the continual erosion and regeneration of discolouration material in drinking water distribution systems' IWA New Developments in IT & Water Conference, Amsterdam 4-6 November 2012

Husband,S., Boxall,J.B., (2012) 'Misleading Velocity Analysis for Water Quality Management in Transmission Mains ' EWRI 2012, Albuquerque 20/24th May

Husband,S., Xin, Y., Boxall,J.B., (2012) 'Long Term Asset Condition and Discolouration Modelling in Water Distribution Systems with Epanet MSX' EWRI 2012, Albuquerque 20/24th May

Husband, S., Jackson, M., Boxall, J. (2011) 'Trunk Main Discolouration Trials and Strategic Planning', Computing and Control for the Water Industry (CCWI) 2011, Exeter 5/7th September

Cook, D. and Boxall, J., (2011) 'Discoloration material accumulation in water distribution systems'. Journal of Pipeline Systems Engineering and Practice, 2 (4), 113–122.

Husband,S (2010) 'Discolouration in Water Distribution Systems; Understanding, Modelling and Practical Applications' Doctoral Thesis, The University of Sheffield

Husband,S., Boxall,J.B., (2011) 'Asset Deterioration and discolouration in water distribution systems' Water Research 45, 113-124 doi:10.1016/j.watres2010.08.021,

Husband,S., Williams, R., Boxall,J.B., (2010) 'Risk Managed Trunk Main Operation' Water Distribution System Analysis 2010, Tucson, Arizona, USA, 12-15 September.

Sharpe, R., Smith, C.J, Biggs, C.A. and J. B. Boxall (2010). Pilot scale laboratory investigations into the impact of steady state conditioning flow on potable water discolouration. Water Distribution System Analysis 2010, Tucson, Arizona, USA, 12-15 September.

Dienes, P., Sekar, R., Husband, S., Boxall, J.B., Osborn, A. M. and Biggs, C.A., (2010) ‘A new coupon design for simultaneous analysis of in situ microbial biofilm formation and community structure in drinking water distribution systems’ Applied Microbiology and Biotechnology 87:749-756 DOI 10.1007/s00253-010-2510-x

Husband,S., Whitehead, J., Boxall,J.B., (2010) 'The Role of Trunk Mains in Discolouration' Journal of Water Management, ICE, DOI: 10.1680/wama.900063

Husband,S., Boxall,J.B., (2010) 'Field Studies of Discolouration in Water Distribution Systems: Model Verification and Practical Implications' Journal of Environmental Engineering 136(1): 86-94 DOI: 10.1061/(ASCE)EE.1943-7870.0000115

Seth, A., Husband,S., J., Boxall,J.B., (2009) 'Rivelin Trunk Main Flow Test' Proc. 10th International Conference on Computing and Control for the Water Industry, CCWI, 1 - 3 September, Sheffield, UK

Husband,S., Whitehead, J., Boxall,J.B., (2009) 'Long Term Trunk Main Monitoring Yields Operational Dividends' 3rd Biennial Conference of the UK Network on Potable Water Treatment & Supply, Buxton, 1,2 June 2009

Husband,S., Boxall, J.B., Saul, A.J. (2008) 'Laboratory Studies Investigating the Processes Leading to Discolouration in Water Distribution Networks' Water Research 42(16): 4309-4318

Husband, P. S. and J. B. Boxall (2008). 'Water Distribution System Asset Deterioration and Impact on Water Quality - a case study' ASCE World Environmental and Water Resources Congress, May 13-16, Ahupua'a, Hawaii, USA

Vreeburg, J. H. G. and J. B. Boxall (2007). 'Discolouration in potable water distribution systems: A review.' Water Research 41: 519-529.

Husband,S., Boxall,J.B., (2007) ‘Repeat DMA Flushing Operations: discolouration comparison, modelling and management’ Proc. EPSRC Develpments in Water Treatment & Supply, 4-5 July 2007, Bath, UK

Boxall,J.B. and Prince, R.A., (2006) ‘Modelling Discolouration in a Melbourne (Australia) Potable Water Distribution System’. Journal of Water Supply: Research and Technology - AQUA, IWA. 55.3, 207-219

Husband,S., Boxall,J.B., (2005) ‘Material Accumulation and Mobilisation in a Pipe Loop System’. Proc. EPSRC Develpments in Water Treatment & Supply, 5 - 6 July 2005, York, UK

Boxall,J.B., Dewis, N. (2005) 'Identification of discolouration risk through simplified modelling' Proc. ASCE, EWRI, World Water and Environmental Resources Congress, May 15-19, Anchorage, Alaska, USA

Boxall,J.B., and Saul, A.J. (2005) ‘Modelling Discolouration in Potable Water Distribution Systems’ Journal Environmental Engineering ASCE. Vol 131, No. 5, 716-725.

Boxall,J.B., Saul, A.J. and Skipworth, P.J. (2004) ‘Modelling for Hydraulic Capacity’ Journal of the American Water Works Association. Vol. 96, No. 4, pp. 161-169.

Boxall,J.B., Skipworth, P.J. and Saul, A.J. (2003)
‘Aggressive flushing for discolouration event mitigation in water distribution networks’ Water Science and Technology - Water Supply Vol. 3; Part 1/2 pp. 179- 186.

Boxall,J.B., Unwin, D.M., Husband, P.S., Saul, A.J., Dewis, N. and Gunstead, J.D. (2003) 'Water quality in distribution systems: rehabilitation and maintenance strategies’ Proc. International CCWI conference, Advances in Water Supply Management, 15 - 17 September 2003, Imperial College London, UK.

Boxall,J.B., Saul, A.J., Gunstead, J.D. and Dewis, N. (2003) ‘Regeneration of discolouration in distribution systems’ Proc. ASCE, EWRI, World Water and Environmental Resources Conference, 23-26 June 2003, Philadelphia, USA.

Seth,A., Bachmann, R.T., Boxall, J.B., Saul, A.J. and Edyvean, R. (2003) ‘Characterisation of Materials Causing Discolouration in Potable Water Systems’ Water Science and Technology, Vol 49, No 2, 27-32

Boxall,J.B., Skipworth, P.J. and Saul, A.J. (2001) 'A Novel Approach to Modelling Sediment Movement in Distribution Mains Based on Particle Characteristics'. Water Software Systems: v. 1: Theory and Applications (Water Engineering & Management). B. Ulanicki, B. Coulbeck and J. P. Rance, Research Studies Press, Hertfordshire, UK. 1: 263-273.